CN111212707A

CN111212707A - Milling assembly comprising imperforate indexable inserts and positioning tool having insert retaining surfaces

Info

Publication number: CN111212707A
Application number: CN201880067075.8A
Authority: CN
Inventors: 吉尔·赫克特
Original assignee: Iscar Ltd
Current assignee: Iscar Ltd
Priority date: 2017-10-16
Filing date: 2018-09-16
Publication date: 2020-05-29
Anticipated expiration: 2038-09-16
Also published as: CA3078336A1; KR102512810B1; IL273409B2; JP7227262B2; TW201922389A; IL273409B1; CN111212707B; KR20200068657A; RU2020110463A3; WO2019077596A1; US10391566B2; IL273409A; RU2020110463A; US20190111502A1; TWI763905B; EP3697571A1; BR112020007407A2; JP2020536762A

Abstract

A positioning tool (16, 116, 216, 316) is configured for holding undersized, imperforate, indexable cutting inserts (14, 114, 214). The cutting insert (14, 114, 214) may have a triangular or triangular shape. The positioning tool (16, 116, 216, 316) has an outwardly facing insert retaining surface (28) with an elongated shape that corresponds to the shape of the side of the undersized cutting insert (14, 114, 214). The positioning tool (16, 116, 216, 316) is configured to hold the cutting insert (14, 114, 214) using magnetic, electrostatic and/or adhesive forces. The milling kit (10) may include such a positioning tool (16, 116, 216, 316) and one or more such undersized cutting inserts (14, 114, 214). The milling kit (10) may also optionally include a milling tool (12) having one or more insert pockets (18) configured to receive such cutting inserts (14, 114, 214), and may also optionally include one or more clamping screws (74) configured to clamp and externally secure such inserts (14, 114, 214) in the pockets (18) without passing through the inserts (14, 114, 214).

Description

Milling assembly comprising imperforate indexable inserts and positioning tool having insert retaining surfaces

Technical Field

The subject matter of the present application relates to milling tools. In particular, the subject matter of the present application relates to a micro milling tool with undersized indexable triangular or triangular milling inserts without through holes for clamping the inserts.

Background

In general, replaceable/non-reusable inserts secured in reusable steel bodies are preferred over one-piece cutting tools in which the tool body has a built-in sharp cutting edge. One-piece tools dominate at the lower end of the tool size/diameter dimension. In particular, this is applicable at certain insert sizes where the use of replaceable inserts is impractical (or even impossible) because they cannot be secured in the slot by a clamping screw that is typically passed through a clamping hole in the insert. The main reason for this is that, at certain sizes, the clamping screw (and in particular its head) is too small for a standard driver or wrench.

Another and perhaps more important problem with replaceable/non-reusable indexable inserts is that it is very difficult to manipulate such small, nearly invisible units by hand. The milling kit of the present application, and in particular the magnetic positioning tool, overcomes these problems and provides a milling tool having replaceable undersized milling inserts.

Disclosure of Invention

According to a first aspect of the subject matter of the present application, there is provided a positioning tool configured to hold and/or bear undersized, imperforate indexable cutting inserts, the positioning tool comprising an outwardly facing insert retaining surface having an elongated shape,

wherein the content of the first and second substances,

the shape of the insert retaining surface corresponds to the shape of the side surface of the cutting insert.

According to a second aspect of the subject matter of the present application, there is also provided a milling kit comprising a positioning tool and an undersized non-porous cutting insert.

According to a third aspect of the subject matter of the present application there is also provided a milling kit comprising a milling tool having an insert pocket, an undersized imperforate indexable cutting insert externally secured in the pocket by a clamping screw, and a locating tool.

According to a fourth aspect of the subject matter of the present application, there is also provided a method of replacing an undersized insert (typically because all cutting edges have worn) with a magnetic locating tool, which may comprise the steps of:

a. attaching a blade retention surface to any portion of an undersized blade;

b. loosening the screw to loosen or release the undersized blade;

c. pulling the blade out of the slot, separating the blade from the blade retaining surface and discarding the blade;

d. attaching an insert retaining surface to an unused relief surface of a replacement cutting insert;

e. insert the replacement insert into the slot and tighten the screw.

According to a fifth aspect of the subject matter of the present application there is also provided a method of indexing an undersized insert (typically due to cutting edge wear) with a magnetic locating tool, the method may comprise the steps of:

a. attaching a magnetic retention surface to an exposed or accessible major relief surface associated with an operative normally worn major cutting edge;

b. loosening the screw to loosen or release the undersized blade;

c. attaching a magnetic tool to the blade;

d. removing the insert from the pocket and indexing it so that the unused major relief surface is attached to the insert retaining surface;

e. the undersized insert 14 is inserted into the slot 18 and the screw tightened.

Any of the following features, alone or in combination, may be applicable to any of the above-described aspects of the subject matter of the present application:

the positioning tool may have a magnetic or magnetized insert retaining surface configured to magnetically hold the insert. In some embodiments, the positioning means may comprise a natural magnet, while in other embodiments, the positioning means may comprise an electromagnet.

The positioning tool may have an electrostatic type blade holding surface configured to hold the blade electrostatically.

The positioning tool may have an adhesive blade holding surface to which the blade may temporarily adhere upon contact.

The insert retaining surface is elongated in an elongation direction, and the positioning tool may further include an opposing enlarged gripping surface extending in the Elongation Direction (ED) and configured to provide a grip and orientation indication when the positioning tool is held by an operator.

The insert holding surface may have two opposite long edges extending in the direction of elongation and two shorter short edges extending between the long edges.

The tool body is elongated in an axial direction away from the locating head, and the insert retaining surface is an outermost surface projecting axially outward from the locating head.

The undersized insert is triangular or trigonal and the insert retaining surface is configured to engage one of the three major relief surfaces of the undersized insert.

The insert retaining surface may comprise opposing identical long edges in the range of 1.8 to 4.2 mm.

The insert retaining surface has opposing short edges connecting the opposing long edges and in the range of 1.1 to 2.4 mm.

The positioning tool may be modular and the tool rear end of the tool body may be configured to be selectively attached and detached from the driving tool.

The positioning tool may have an elastic sleeve rigidly connected to the positioning head.

The tool body is elongated in an axial direction away from the locating head; the insert retaining surface is elongated in an elongation direction; and the footprint of the insert retaining surface is smaller than the footprint of the tool body in a view in the axial direction.

The locating head may include two head surfaces extending rearwardly and diverging away from the blade retention surface.

The positioning tool may further comprise a non-ferromagnetic, non-magnetic holding portion rigidly connected to the tool body and configured for effecting gripping and applying torque transmission.

The cutting insert has only three main cutting edges and an inscribed circle in tangential contact with all three main cutting edges.

The inscribed circle may have an inscribed circle diameter in the range of 2.5mm to 3.8 mm.

The inscribed circle may have an inscribed circle diameter in the range of 2.5mm to 3.2 mm.

The shape of the insert retaining surface corresponds to the shape of the major relief surface of the cutting insert.

The cutting insert includes:

opposing insert top and bottom surfaces and an insert peripheral surface extending therebetween;

a central axis of symmetry passing through the top and bottom surfaces; and

a maximum blade thickness, measured along the central axis of symmetry, in the range of 1mm to 2.5 mm.

The milling tool may comprise a fluid channel leading to at least one insert pocket at a fluid outlet.

The cutting insert may have a main cutting edge having a main cutting edge length in the range of 2mm to 4 mm.

The cutting insert includes a central axis of symmetry through the top and bottom surfaces about which the cutting insert has 120 degree rotational symmetry.

Drawings

For a better understanding of the subject matter of the present application and to show how the same may be carried into effect in practice, reference will now be made to the accompanying drawings, in which:

FIG. 1 is an isometric view of a milling kit including an undersized insert and a positioning tool having an insert retaining surface;

FIG. 2 is an isometric view of a first and/or second embodiment of a positioning tool having a drive device;

FIG. 3 is an axial view of the magnetic tool of FIG. 2;

FIG. 4 is a side view of the first embodiment of the positioning tool of FIG. 2;

FIG. 5 is a third embodiment of the positioning tool without the drive device;

FIG. 6 is an exploded isometric view of a first embodiment of an undersized insert and milling tool;

FIG. 7 is a side view of the milling tool of FIG. 6;

FIG. 8 is an axial view of the milling tool of FIG. 6;

FIG. 9 is a side view of the undersized blade of FIG. 6;

FIG. 10 is a plan view of the insert top surface of the undersized insert of FIG. 6;

FIG. 11 is an exploded isometric view of a second embodiment of an undersized insert and milling tool;

FIG. 12 is a side view of the milling tool of FIG. 11;

FIG. 13 is an axial view of the milling tool of FIG. 11;

FIG. 14 is a side view of the undersized blade of FIG. 11;

FIG. 15 is a plan view of the insert top surface of the undersized insert of FIG. 6; and

fig. 16 is a cross-sectional view of the fluid passageway taken along line XVI-XVI of fig. 7.

Where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.

Detailed Description

In the following description, various aspects of the subject matter of the present application will be described. For purposes of explanation, specific configurations and details are set forth in sufficient detail to provide a thorough understanding of the subject matter of the present application. It will also be apparent, however, to one skilled in the art that the subject matter of the present application may be practiced without the specific configurations and details presented herein.

Refer to fig. 1 and 2. The new milling kit 10 for the milling tool 12 (see fig. 6 and 7) includes one or more undersized, imperforate, indexable milling inserts 14 and a positioning tool 16 for manipulating the inserts into and out of the slots 18 of the milling tool 12.

Undersized blades 14 are indexable, imperforate, positive (positive) and triangular or triangular. The insert 14 is secured in a pocket 18 of the milling tool 12. The milling tool 12 has a longitudinal axis of rotation a.

The term "undersized" is used in the sense of describing a cutting insert 14 that is smaller than currently available replaceable "one-piece" (i.e., not brazed or made from two or more major parts) including a clamping hole. In other words, these undersized blades 14 are so small that they may be swallowed or lost from view between the two fingertips or finger bells. These indexable inserts 14, and particularly their cutting edges, are difficult to see with the naked eye under many lighting conditions. This is particularly problematic when distinguishing between new unused cutting edges and worn cutting edges. These physical characteristics present significant difficulties for the operator to manipulate the tools and blades.

For the purposes of this disclosure, a blade is said to be "undersized" if it meets one or more predetermined dimensional and geometric criteria, as will be further described below.

Thus, the milling tool 12 is provided with a positioning tool 16 (fig. 1 to 5). Indexing, mounting or replacement of these undersized inserts 14 is accomplished with at least the locating tool 16, and the locating tool 16 is used optimally in conjunction with two fingers, as will be further described below.

The positioning tool 16 is configured to hold the undersized insert 14 so that the cutting edge is visible (as opposed to holding the insert 14 by hand, the cutting edge becomes completely invisible while holding the insert 14 by hand). In addition, the positioning tool 16 is configured to hold the insert 14 in a particular orientation to accurately secure and position the insert 14 in the pocket 18 and to accurately identify worn cutting edges. For example, if the cutting edge is worn, the operator holds the insert 14 with the positioning tool 16 by the relief surface associated with the worn cutting edge of the insert 14, removes the insert 14 from the pocket 18, changes the orientation of the insert 14 relative to the positioning tool 16, and then places the insert 14 back in the pocket 18 in the desired orientation (i.e., with the unused cutting edge facing outward).

Most operators will find it difficult, if not impossible, to position, hold and index these undersized inserts 14 without the positioning tool 16.

Thus, according to one embodiment of the subject matter of the present application, the positioning tool 16 is provided as part of a milling kit 10 that includes the positioning tool 16, the milling tool 12, and one or more undersized inserts 14. According to another embodiment, the milling kit 10 comprises only the positioning tool 16 and the undersized insert 14.

Refer to fig. 1 to 2. The positioning tool 16 has opposite tool forward and rearward ends 20 and 22. The positioning tool 16 has a positioning head 24 at the tool front end 20 that has an integral, one-piece construction. The positioning tool 16 includes a tool body 26 at the tool rear end 22 that is rigidly and permanently attached to the positioning head 24. The tool body 26 may be made of plastic or a suitable non-magnetized, non-ferromagnetic material.

The positioning head 24 has an elongated, preferably cylindrical shape. The locating head 24 has an insert retaining surface 28 located at the tool forward end 20 and facing axially outward.

For the purposes of this specification, an "insert retaining surface" is a surface that holds an undersized insert by applying an attractive force to the surface of the insert. The blade holding surface holds the blade by means of an attractive force such as a magnetic force or an electrostatic force. Alternatively, the blade holding surface may be an adhesive surface that temporarily adheres to the blade upon contact.

The insert retaining surface 28 projects axially outwardly from the locating head 24. In other words, the insert retaining surface 28 is the outermost portion of the positioning head 24 in the axial direction thereof. This facilitates better undisturbed retention of the blade 14 and better definition and viewing of its orientation. The insert retaining surface 28 is configured to engage and retain the undersized insert 14. Thus, the insert retaining surface 28 has an asymmetrical shape that is configured to match or correspond to the shape of the side or peripheral side of the undersized insert 14 (typically, most inserts have an elongated side or peripheral side). In particular, the insert has an elongated shape, at least in a plan view of the flank face of the insert (as opposed to a view of the rake face of an insert where symmetrical shapes are quite common).

In a preferred embodiment, described further below, the attractive force is magnetic. Thus, the positioning tool 16 is a magnetic positioning tool 16 having a positioning head 24 with a magnetic insert retaining surface 28. In such embodiments, the head 24 and the insert retaining surface 28 generate a magnetic field formed from a natural magnetic or ferromagnetic material. Additionally, in some embodiments, the magnetic positioning tool 16 may include an electromagnet.

Refer to fig. 3. In plan view, the magnetic blade retention surface 28 has a peripheral edge with a closed elongated shape defining an elongation direction ED. In other words, in a first direction (the elongated direction ED), the shape of the magnetic insert retaining surface 28 has a maximum dimension that is greater than a maximum dimension in a second direction perpendicular to the elongated direction ED. The magnetic insert retaining surface 28 is shaped to correspond or match the side of the undersized insert 14. Specifically, in the attached position (when the magnetic insert retaining surface 28 is in contact with the side of the undersized insert), the undersized insert 14 aligns with and corresponds to the direction of elongation ED (seen in fig. 3) due to the attractive force. The term "corresponding" is used in the sense of denoting a similarity in geometry between the shape of the magnetic insert retaining surface 28 and the shape of the sides of the undersized insert 14 (e.g., if one shape is rectangular, the corresponding shape will not be circular). This is advantageous because when the magnetic insert retaining surface 28 is close enough to any side or side peripheral surface or flank surface 82 of the undersized insert 14, the magnetic pull (primarily within the boundaries of the magnetic insert retaining surface 28) can change the orientation of the insert 14 to match or correspond with the orientation of the magnetic insert retaining surface 28.

In addition, the magnetic positioning tool 16 includes a retaining portion 30 that includes opposing gripping surfaces 32 that provide a grip for an operator and enable torque to be easily applied to the magnetic positioning tool 16. The retention portion 30 is disposed rearwardly away from the magnetic blade retention surface 28. The opposing gripping surface 32 extends in an elongated direction ED. The gripping surface 32 may be parallel to the elongated direction ED. This feature is advantageous because the operator can easily determine or infer the orientation of the magnetic blade retention surface 28 and subsequently the orientation of the undersized blade 14.

The magnetic insert retaining surface 28 has the same or a smaller area than the axial cross-section of the locating head 24. In other words, the magnetic insert retaining surface 28 has a minimum footprint of the magnetic positioning tool 16 in its axial view or in a plan view of the magnetic insert retaining surface 28.

Reference is again made to fig. 3. For example, the magnetic insert retaining surface 28 may have a generally rectangular shape with a pair of opposing long edges 36 and a pair of opposing short edges 38 (which may be non-straight) extending in the elongated direction ED. The positioning head 24 may include head surfaces 34 that each extend from a respective long edge 36. The head surface 34 diverges away from the magnetic insert retaining surface 28. The head surface 34 may be planar and configured to assist an operator in determining the correct orientation and indexed position of the current magnetically held microblade 14 (particularly when the operator indexes the blade 14).

According to the subject matter of the present application, the magnetic positioning tool 16 may have three magnetic positioning tool embodiments:

according to a first magnetic positioning tool embodiment, the magnetic positioning tool 116 is modular and can be rigidly attached/reattached to most of the drivers 42 or tools. Specifically, the tool rear end 122 is configured to attach or clamp onto/into the driver rear end 44 (non-driving end). For example, the tool rear end 122 may include a non-magnetic, non-ferromagnetic coupling portion or sleeve 40 configured to couple or attach the magnetic tool 116 to another tool, such as the driver 42.

According to a second magnetic positioning tool embodiment, the magnetic positioning tool 216 has a positioning head 24 which is an integral part of the driver 242, in particular of the driver rear end 244 (i.e. its non-driving end). For example, the magnetic tool 216 may be attached, pressed into a dedicated recess, or screwed into or onto the driver rear end 44.

According to a third magnetic positioning tool embodiment, the magnetic positioning tool 316 is a stand-alone tool configured to only assist an operator in positioning, holding, and indexing the blade 14 as described above. According to this embodiment, the magnetic tool 316 does not include any drive means, such as a Torx interface/wrench. The magnetic positioning tool 316 includes a retaining portion 330 at the tool rear end 322.

Undersized inserts 14 are typically made of extremely hard and wear resistant materials (e.g., cemented carbide) by pressing and sintering carbide powders in a binder. The cemented carbide may be, for example, tungsten carbide. The milling insert 14 may be coated or uncoated. The undersized blade 14 is preferably unmagnetized. However, during testing, the magnetic locating tool 16 is fully functional and even a demagnetized blade is properly retained.

The undersized insert 14 has opposing insert top and bottom surfaces 48, 50 and an insert peripheral surface 52 extending therebetween. The insert 14 has 120 degree rotational symmetry about a central axis of symmetry CA that passes through the insert top and bottom surfaces 48, 50. Thus, the insert 14 may be indexed three-way about its central axis of symmetry CA. An imaginary median plane MP of the insert 14 is perpendicular to the central axis CA, is located midway between the insert top and bottom surfaces 48, 50, and intersects the insert peripheral surface 52. The maximum insert thickness MIT is measured in a direction parallel to the central axis CA between the outer ends of the insert top and bottom surfaces 48, 50. The maximum blade thickness MIT is preferably in the range of 1.0mm to 2.5 mm.

The insert top surface 48 has a peripheral top edge 54. The top edge 54 includes exactly three operative portions 56 configured for performing operations on a workpiece. For example, each operative portion 56 may include, for example, a major cutting edge 58, a corner cutting edge 60, and/or an inclined cutting edge 62. Each operative portion 56 may include a wiper edge 64 that is not configured to remove material, but rather to smooth or improve the surface quality of the workpiece.

The main cutting edge length CEL of each main cutting edge 58 may be in the range of 2 to 4 mm.

The insert top surface 48 includes a top abutment surface 68 configured for abutting engagement with the screw 74 to secure the insert 14 in the pocket 18. Each top abutment surface 68 comprises exactly three top abutment sub-surfaces 76.

The insert top surface 48 includes a primary rake surface 70 that may be located between the top edge 54 and the top abutment surface 68. Each major rake surface 70 extends from a respective major cutting edge 58.

According to the present embodiment, the insert 14 may have an irregular triangular or regular triangular shape in a top or plan view of the insert top surface 48. An inscribed circle IC is defined between (or tangent to) three identical major cutting edges 58 of the top edge 54. The inscribed circle diameter ICD of the inscribed circle IC is in the range of 2.5 to 3.8mm and preferably between 2.5 and 3.2.

In most or all instances, the range of inscribed circle diameters ICD does not leave room for a suitable functional clamping hole (capable of accommodating a suitable/available screw having a usable screw head size) while maintaining a suitable blade configuration. In other words, an insert that is too small may become too weak and unusable, and/or the clamping hole may only accommodate a screw that is too small and not suitable for securing the cutting insert in the slot. Thus, these inserts 14 are free of clamping holes and any other through holes and are therefore considered "imperforate". The absence of a clamping hole is advantageous at least because the insert is stronger and less expensive to manufacture than an insert having a hole.

The bottom surface 50 includes a bottom abutment surface 78. The bottom abutment surface 78 is preferably planar. The bottom surface 50 has a bottom edge 80 that may lie in a single plane. The bottom edge 80 is not configured for any type of machining. Thus, the blade 14 is single-sided or one-sided. The bottom surface 50 may include a recess centrally located in the bottom abutment surface 78 that may improve the definition of engagement between the bottom abutment surface 78 and a corresponding abutment surface in the groove 18 (three-point engagement as is known in the art).

It should therefore be noted that an undersized insert 14 may have a top and/or bottom surface provided with recesses, depressions, and other structures, but may still be considered "imperforate" so long as it lacks a through hole of sufficient size to allow a clamping element to pass through and secure the insert in the insert pocket.

The insert peripheral surface 52 includes relief surfaces 82, each extending from a respective portion of the top edge 54. The flank surface 82 converges downwardly (as it approaches the central axis CA) toward the bottom edge 80. Accordingly, the insert 14 is defined as a positive insert 14 or an insert having a positive cutting geometry, as is known in the art.

Refer to fig. 6 to 10. According to the first insert embodiment, the undersized insert 14 is a high feed milling insert 114 as is known in the art. Each operative portion 156 includes an inclined cutting edge 162 that connects transversely (seen in plan view in the insert top surface 148 in fig. 10) to a main cutting edge 158 that connects to a corner cutting edge 160. The operative portion 156 may include a minor corner cutting edge 166 connecting the inclined cutting edge 162 with the major cutting edge 158. Each inclined cutting edge 162 is formed at the intersection between an inclined rake surface 184 and an inclined relief surface 186. Each major cutting edge 158 is formed at the intersection between a major rake surface 170 and a major relief surface 172. The major relief surface 172 is configured for abutment with the insert retaining surface 28 of the magnetic positioning tool 16. Each corner cutting edge 160 is formed at the intersection between a corner rake surface 188 and a corner relief surface 190. Each rake surface is formed on the insert top surface 148. Each flank surface is formed on the insert peripheral surface 152.

Refer to fig. 11 to 15. According to a second blade embodiment, the undersized blade 14 is a shouldering (shouldering) blade 214 known in the art. The shoulder machining insert is configured to form a 90 degree shoulder in the workpiece. Each operative portion 256 includes a main cutting edge 258, a wiper edge 264 and a corner cutting edge 260 extending therebetween. Each operative portion 256 may also include an inclined cutting edge 262 extending between the wiper edge 264 and the main cutting edge 258 of the adjacent operative portion 256. Each major cutting edge 258 is formed at the intersection between a major rake surface 270 and a major relief surface 272. Each inclined cutting edge 262 is formed at the intersection between an inclined rake surface 284 and an inclined relief surface 286. Each corner cutting edge 260 is formed at the intersection between a corner rake surface 288 and a corner relief surface 290. Each rake surface is formed on the top surface 248. Each flank surface is formed on the insert peripheral surface 252. The peripheral surface 252 also includes wiper relief surfaces 265, each extending from a respective wiper edge 264.

In the first and second embodiments, the inscribed circle diameters ICD are 3.0mm and 2.8mm, respectively.

Refer to fig. 6 and 11. The milling tool 12 has a milling body 91 and a cutting portion 92 extending therefrom that includes at least two flutes 18. The groove 18 or grooves are referred to in the art as radially oriented grooves or radial grooves 18. Accordingly, the blade 14 is also referred to as a radial blade.

Each slot 18 may have a slot floor 93 and two slot walls 94 extending therefrom. The slot wall 94 may be perpendicular to the slot floor 93. According to an embodiment of the first blade 114, the two slot walls 194 converge inwardly in a direction parallel to the axis of rotation a (seen in fig. 6). According to the second embodiment of the insert 214, the two groove walls 294 converge inwardly in a direction perpendicular to the axis of rotation a (seen in fig. 11).

Each slot 18 includes a wedge-type structure that secures these undersized imperforate blades 14. The insert 14 is not attached or brazed to any other part of the milling tool 12 or any type of adapter/holder in any way to ensure simple, quick and cost-effective replacement or indexing of the insert 14 itself (without the need for any adapter or shim). Each slot 18 includes a screw 74, the screw 74 being screwed into a threaded hole 95 of the milling tool 12 without passing through the insert 14. The threaded hole 95 is not located in the slot floor 93. The screw 74 is configured to directly contact the insert 14 and force the insert 14 against the slot bottom surface 93 (i.e., the insert 14 is wedged therebetween). The screw 74 also pulls the insert 14 toward the slot wall 94 that positions the insert 14 in the slot 18 and against the slot wall 94. When tightened, the screw 74 engages the top abutment surface 68, and in particular, the screw 74 abuts one of the top abutment sub-surfaces 76.

Each slot 18 may also include an internal fluid passage 96 extending along the milling body 91 and opening into the slot 18 at a fluid outlet 98. The fluid outlet may be located near the threaded bore 95. The fluid passage 96 and the fluid outlet 98 are separate from the threaded bore 95. The fluid channel 96 may be located between two slot walls 94.

Torque drivers are well known and are sometimes provided/recommended for use with tools in the current field (i.e., micro milling tools including small screws) because such small diameter fasteners can be easily torn or broken. These torque drivers include torque limiting mechanisms that are calibrated to prevent an operator from exceeding a recommended torque limit when applying torque to the respective screw size.

The standard/conventional driver 42 or torque driver includes opposite driver front and

rear ends

43, 44 and a driver body 46 extending therebetween. The drive 42 has a drive axis of rotation DRA. The driver front end 43 includes a wrench or torque transmission geometry, e.g. TORX^TM. The driver body 46 includes a driver retention portion 30 that is configured to provide a grip. The drive retaining portion 30 may extend radially outward away from the drive rotational axis DRA on one or both of its opposite sides.

The method of replacing an undersized insert 14 with a magnetic locating tool 16 (typically because all cutting edges have worn) may include the steps of:

a. attaching the blade retention surface 28 to any portion of the undersized blade 14;

b. loosening the screw 74 to loosen or release the undersized insert 14;

c. pulling the blade 14 out of the slot 18, separating the blade 14 from the blade retention surface 28 and discarding the blade;

d. attaching the insert retaining surface 28 to an unused relief surface 82 of a replacement cutting insert;

e. the replacement insert 14 is inserted into the slot 18 and the screw 74 is tightened.

The method of indexing the undersized insert 14 (typically due to worn cutting edges) with the magnetic locating tool 16 may include the steps of:

a. attaching the magnetic retention surface 28 to an exposed or accessible major relief surface 72 associated with the operative normally worn major cutting edge 25;

b. loosening the screw 74 to loosen or release the undersized blade 14;

c. attaching the

magnetic tool

16, 116, 216, 316 to the blade 14;

d. removing the insert 14 from the pocket (18) and indexing it so that the unused major relief surface (72, 172, 272) is attached to the insert retaining surface (28);

e. the undersized insert 14 is inserted into the slot 18 and the screw 74 is tightened.

Claims

1. A positioning tool (16, 116, 216, 316) configured to hold undersized, imperforate, indexable cutting inserts (14, 114, 214), the positioning tool (16, 116, 216, 316) comprising:

a tool body (26) having a tool front end (20) and a tool rear end (22);

a positioning head (24) provided at the tool tip (20) of the tool body (26); and

an outwardly facing insert retaining surface (28) provided on the locating head (24), wherein:

the insert retaining surface (28) has an elongated shape corresponding to the shape of the side of the cutting insert (14, 114, 214); and is

The insert retaining surface (28) exerts an attractive force for orienting and retaining the cutting insert (14, 114, 214).

2. The positioning tool (16, 116, 216, 316) according to claim 1, wherein:

the attractive force is magnetic force;

the positioning means is a magnetic positioning means (16, 116, 216, 316); and is

The insert retaining surface (28) is a magnetic insert retaining surface (28).

3. The positioning tool (16, 116, 216, 316) according to claim 1 or 2, wherein:

the insert retaining surface (28) is elongated in an Elongation Direction (ED); and is

The positioning tool (16, 116, 216, 316) further includes an opposing enlarged gripping surface (32) extending in an Elongated Direction (ED) and configured to provide a grip and an orientation indication when the positioning tool (16, 116, 216, 316) is held by an operator.

4. The positioning tool (16, 116, 216, 316) according to any one of claims 1 to 3, wherein:

The insert retaining surface (28) comprises two opposite long edges (36) extending in an Elongation Direction (ED) and two shorter short edges (38) extending between the long edges (36).

5. The positioning tool (16, 116, 216, 316) according to any one of claims 1-4, wherein the tool body (26) is elongate in an axial direction extending away from the positioning head (24), and the insert retaining surface (28) is an outermost surface projecting axially outwardly from the positioning head (24).

6. The positioning tool (16, 116, 216, 316) according to any one of claims 1 to 5, wherein:

the undersized blade (14) is triangular or trigonal, and

the insert retaining surface (28) is configured to engage one of the three major relief surfaces (72, 172, 272) of the undersized insert (14).

7. The positioning tool (16, 116, 216, 316) according to any one of claims 1-6, wherein the insert retaining surface (28) comprises opposing identical long edges (36) in the range of 1.8mm to 4.2 mm.

8. The positioning tool (16, 116, 216, 316) according to claim 7, wherein the insert retaining surface (28) comprises opposing short edges (38) connecting the opposing long edges and being in the range of 1.1 to 2.4 mm.

9. The positioning tool (16, 116, 216, 316) according to any one of claims 1 to 8, wherein the positioning tool (16, 116, 216, 316) is modular and the tool rear end (22) of the tool body (26) is configured to be selectively attached and detached from the drive tool (42).

10. Positioning tool (16, 116, 216, 316) according to claim 9, wherein the positioning tool (16, 116, 216, 316) comprises an elastic sleeve (40) rigidly connected to the positioning head (24).

11. The positioning tool (16, 116, 216, 316) according to any one of claims 1 to 10, wherein:

the tool body (26) is elongated in an axial direction away from the positioning head (24);

The footprint of the insert retaining surface (28) is smaller than the footprint of the tool body (26) in a view in the axial direction.

12. The positioning tool (16, 116, 216, 316) according to any one of claims 1 to 11, wherein:

the locating head (24) includes two head surfaces (34) extending rearwardly and diverging away from the insert retaining surface (28).

13. The positioning tool (16, 116, 216, 316) according to any one of claims 1 to 12, further comprising:

a non-ferromagnetic, non-magnetic retaining portion (30) rigidly connected to the tool body (26) and configured for effecting gripping and applying torque transmission.

14. A milling kit (10) for a milling tool (12), the milling tool (12) having at least one insert pocket (18), the milling kit (10) comprising:

-a positioning tool (16, 116, 216, 316) according to any of claims 1 to 13; and

at least one undersized, non-porous indexable cutting insert (14) configured to be carried by a positioning tool (16, 116, 216, 316).

15. The milling kit (10) according to claim 14, wherein the cutting insert (14) comprises only three major cutting edges (58) and an Inscribed Circle (IC) in tangential contact with all three major cutting edges (58).

16. The milling kit (10) according to claim 15, wherein the Inscribed Circle (IC) has an Inscribed Circle Diameter (ICD) in the range of 2.5mm to 3.8 mm.

17. The milling kit (10) according to any one of claims 14 to 16, wherein an Inscribed Circle Diameter (ICD) of the Inscribed Circle (IC) is in a range of 2.5mm to 3.2 mm.

18. The milling kit (10) according to any one of claims 14 to 17, wherein the insert retaining surface (28) has a shape that corresponds to the shape of the major relief surface (72, 172, 272) of the cutting insert (14).

19. The milling kit (10) according to any one of claims 14 to 18, wherein the cutting insert (14) comprises:

opposing insert top (48) and bottom (50) surfaces and an insert peripheral surface (52) extending therebetween;

a central axis of symmetry (CA) passing through the top and bottom surfaces; and

a Maximum Insert Thickness (MIT) measured along the center axis of symmetry (CA) in the range of 1mm to 2.5 mm.

20. The milling kit (10) according to any one of claims 14 to 19, wherein the milling tool (12) comprises a fluid channel (96) leading to the at least one insert pocket (18) at a fluid outlet (98).

21. The milling kit (10) according to any one of claims 14 to 20, wherein the cutting insert (14) comprises a main cutting edge (58, 158, 258) having a main Cutting Edge Length (CEL) in the range of 2mm to 4 mm.

22. The milling kit (10) according to any one of claims 14 to 21, wherein the cutting insert (14) comprises:

opposing insert top (48) and bottom (50) surfaces and an insert peripheral surface (52) extending therebetween; and

a central axis of symmetry (CA) through the top and bottom surfaces about which the cutting insert (14) has 120 degree rotational symmetry.

23. The milling kit (10) according to any one of claims 14 to 22, further comprising:

a milling tool (12) has an insert pocket (18) configured and dimensioned to receive a cutting insert (14).

24. A method of indexing or replacing an undersized, imperforate, indexable cutting insert (14), the cutting insert (14) being secured externally to an insert pocket (18) of a milling tool (10) by a clamping screw (74), the method comprising:

a. providing a positioning tool (16, 116, 216, 316) according to any one of claims 1 to 13;

b. contacting the exposed major relief surface (72, 172, 272) of the operative major cutting edge (158, 258) of the insert with an insert retaining surface (28) of a locating tool, thereby seating the cutting insert (14);

c. loosening the clamping screw (74) to release the cutting insert (14) from the insert pocket (18);

d. removing the cutting insert (14) from the pocket (18) with a locating tool and indexing or replacing the cutting insert (14) by hand so as to attach and be carried by the major relief surface (72, 172, 272) of the unused cutting edge to the insert retaining surface (28) of the locating tool;

e. inserting the indexed or replacement cutting insert (14) into the slot (18) with a locating tool; and

f. the clamping screw (74) is tightened to secure the cutting insert (14) to the insert pocket (18).